Ti-6Al-4V (Grade 5) Titanium: Properties, Standards, and Applications Explained

(Updated September 2026)

Ti-6Al-4V (Grade 5) is the alpha-beta titanium alloy that accounts for roughly half of all titanium consumed worldwide, combining a tensile strength of roughly 900-950 MPa with a density near 4.43 g/cm³. That strength-to-weight profile, not a single “best titanium” claim, is why it dominates aerospace, medical implant, marine, and now additive-manufacturing applications where nearly every other titanium grade gets compared against it as the baseline.

Ti-6Al-4V (Grade 5) is the most widely used titanium alloy in the world — often shortened to Ti64 titanium in machine shops and mill certs, and just as often typed as ti6al4v grade 5 or ti-6al-4v grade 5 without the parentheses, or as 6Al-4V titanium with the “Ti” dropped — and understanding why starts with a single structural fact: it’s one of the only common titanium grades built from two crystal phases instead of one. That two-phase design is the root cause of nearly every property difference discussed in this guide — from why Grade 5 is stronger than commercially pure titanium, to why its heat-treatment response is more complex, to why an ELI variant exists at all. This guide walks through composition, mechanical and physical properties, the standards that govern it, where it’s actually specified, and the questions buyers ask most.

What Is Ti-6Al-4V (Grade 5) Titanium? (Composition and Classification)

Ti-6Al-4V — also written Ti6Al4V, TC4, or Ti 6Al-4V depending on the standard or region — is an alpha-beta titanium alloy. Its chemical composition is roughly 90% titanium, 5.5-6.75% aluminum, and 3.5-4.5% vanadium (UNS R56400), plus tightly controlled limits on iron, oxygen, carbon, nitrogen, and hydrogen per ASTM B265. The aluminum stabilizes the alpha phase and the vanadium stabilizes the beta phase, and that division is the reason the alloy behaves so differently from commercially pure (CP) titanium.

The Dual-Phase Advantage. CP titanium Grades 1 through 4 are single-phase alpha alloys — they get stronger as more interstitial oxygen and iron are allowed into the specification, but they stay one crystal structure throughout. Ti-6Al-4V is deliberately alloyed to hold a mix of alpha and beta phases at room temperature. That dual-phase structure is what allows Grade 5 to be heat-treated for additional strength, which CP titanium largely can’t be. It’s the underlying reason every heat-treatment, corrosion, and machining difference in this guide traces back to composition, not a marketing claim about “the best titanium.”

A designation number does not replace a product-form specification, delivery condition, dimension, test, or sector-specific requirement, and two mill certificates reading “ASTM Grade 5” can describe significantly different mechanical properties, depending on whether it’s sheet, round bar, forging, or additively manufactured, and whether it was supplied annealed or solution-treated-and-aged. You will see that distinction repeated throughout this guide.

Mechanical and Physical Properties

In the standard wrought, mill-annealed condition per SAE AMS 4967, Ti-6Al-4V typically shows an ultimate tensile strength in the 900-950 MPa range and a yield strength around 828-920 MPa. Elongation runs roughly 10-18%, depending on product form and test orientation. Density is approximately 4.43 g/cm³, about 56% that of steel, and that combination of density and tensile strength gives the alloy its defining strength-to-weight advantage. Elastic modulus runs 104-120 GPa, and hardness sits at HRC 30-34 annealed, rising to HRC 35-39 after heat treatment.

These ranges span multiple independent secondary sources rather than a single cross-validated figure, so treat the low end and high end as real variation, not measurement noise — the exact value on your mill cert depends on product form, orientation, and delivery condition, which is exactly why the certificate matters more than the grade name alone.

Grade 5 vs. Grade 23 (ELI): What Actually Changes

The grade 5 vs grade 23 titanium question sounds like it should be complicated, but Grade 23 (Ti-6Al-4V ELI) actually shares the same base chemistry as standard Grade 5. The difference that actually matters is a single tightened composition limit — The Interstitial Trade-Off. ELI stands for Extra Low Interstitial, and the governing specification, ASTM F136, holds interstitial elements (chiefly oxygen, but also iron and nitrogen) to a lower ceiling than the standard Grade 5 specifications. Lower interstitial content improves fracture toughness and fatigue performance at the cost of some strength, which is why ELI is specified as the biocompatible titanium option of choice for fracture-critical medical implants rather than a marketing upgrade.

ASTM F136-26 — a 2026 edition, confirmed active as of February 2026 — is the current governing specification for wrought Ti-6Al-4V ELI in surgical implant applications, covering strip, sheet, plate, bar, forging bar, and wire. On the ELI side, AMS 4930 covers Ti-6Al-4V ELI bars, wire, forgings and rings; on the standard side, AMS 4967 (current revision N, issued 2022) covers the standard, non-ELI version of the same product forms in an annealed, heat-treatable condition. It’s an easy pair to mix up on a purchase order, and the two specifications are not interchangeable.

If your application is fracture-critical or implant-grade, specify ELI and cite ASTM F136 by its current edition. If it’s a general structural or aerospace application without a fracture-toughness driver, standard Grade 5 under AMS 4967 or AMS 4928 is the more common choice.

How Grade 5 Compares to Other Titanium Grades

A titanium grades comparison starts from one fact: as an alpha-beta alloy, the grade 5 titanium alloy sits in a family of ASTM/UNS titanium alloy grades — from soft, highly formable commercially pure titanium through Grade 23/ELI (SAE AMS 4930) to higher-alloy variants for specific service conditions. The Titanium Grade Roster below places Grade 5 in that context using cross-validated figures where available and clearly qualified language where a precise number isn’t independently confirmed.

Grade 6 and Grade 9 figures above are presented qualitatively rather than as precise numbers because independent sources describe their positioning consistently (“medium strength between Grade 4 and Grade 5” for Grade 9) but don’t converge on one exact tensile value — treat those two rows as directional, not spec-sheet precision. A grade designation is a starting point for a conversation with your mill or fabricator, not a substitute for the actual product-form specification.

Heat Treatment and Microstructure

Beyond which grade a mill cert lists, how that grade was heat-treated changes its numbers just as much. Ti-6Al-4V’s beta transus — the temperature above which the alloy is fully beta phase — is commonly cited in the 995-999°C range, cross-checked against a NIST publication and a mill datasheet. In Fahrenheit, that’s roughly 1,823-1,830°F (995°C × 9/5 + 32 = 1,823°F). Below that temperature, the alloy holds its two-phase alpha-beta structure. A peer-reviewed heat-treatment study independently confirms this envelope: primary and secondary alpha were dominant in samples heat-treated at 850°C and 930°C, while Widmanstätten and basket-weave alpha structures dominated in a sample heat-treated above the beta transus, at 1,066°C.

These are the two most common conditions on mill certs: annealed, the standard delivery condition that will give you the balanced strength/ductility values in the properties table above, and solution-treated-and-aged (STA, also written as solution treatment and aging). Solution treatment heats the material into or near the beta field, usually ending with a water quench; the subsequent aging heat treatment step precipitates more alpha at a lower temperature, increasing strength and fatigue strength at some expense to ductility. Which condition you get modifies the actual mechanical properties far more than the grade designation — two “Grade 5” bars in different conditions aren’t interchangeable for a fatigue-critical application.

The practical point: when a spec sheet notes one single tensile value for “Ti-6Al-4V”, ask which condition it refers to. Annealed and STA material from the same heat may vary by well over 100 MPa in yield strength.

Corrosion Resistance and Service Limits

Heat-treatment condition isn’t the only spec-sheet detail that needs qualifying. Ti-6Al-4V isn’t universally corrosion-resistant, despite how often supplier literature markets “exceptional corrosion resistance” without qualifying the environment. Titanium’s thin oxide film is chemically inert and self-healing in most oxidizing and neutral environments. That’s the real, well-documented mechanism behind the alloy’s good general corrosion resistance and seawater performance. But the same alloy is also vulnerable to attack in reducing acids — hydrofluoric, hydrochloric, sulfuric, and phosphoric among them — and in dry chlorine, where the protective film can’t re-form as it does in oxidizing conditions.

The same passive-film mechanism has a second, less obvious failure mode. Peer-reviewed research into Ti-6Al-4V dental implants found that inflammatory, low-oxygen biological environments — and exposure to hydrogen peroxide — can measurably degrade the alloy’s protective oxide film, increasing corrosion products even in implant-grade material. In other words, “excellent corrosion resistance” is a statement about a specific environment, not a fixed property of the metal.

Service-temperature limits matter just as much: Ti-6Al-4V is generally rated for continuous service up to roughly 400°C (750°F). Beyond that, mechanical properties and oxidation resistance both decline. If your application involves reducing acids, dry chlorine, sustained temperatures above 400°C, or a biologically inflammatory environment, corrosion performance needs to be verified for that specific condition, not assumed from the alloy’s general reputation.

Machining, Forming, and Welding

Machining Ti-6Al-4V is genuinely more difficult than machining steel, but the reason is more specific than “it’s a tough metal.” Titanium’s thermal conductivity is roughly a sixth that of steel, so heat generated at the cutting edge doesn’t vent into the chip the way it does with steel. Instead it builds up at the tool tip. The alloy also work-hardens quickly: a light or rubbing pass can work-harden the surface 10-20% almost immediately, making the next small pass harder, not easier. That pair of factors makes tool wear, not raw hardness, usually the real limiting factor.

That said, wear isn’t a simple function of cutting speed. A high-speed machining study (100-300 m/min) found that raising the cutting length from 40 mm to 120 mm increased crater wear over 150% and flank wear by 40%. Once parameters were optimized, depth of cut and cutting length affected wear more significantly than cutting speed alone. Practical Machinist’s forum practitioner’s advice supports this with tangible figures: roughly 90-100 SFM with uncoated carbide tooling, or 60-80 SFM as a conservative starting point for better tool life, with water-soluble flood coolant.

For hot forming, published research reports an optimum condition near 700°C with a 150-second hold for springback reduction; a multistage V-roll process achieved 15% tighter profile radius and 35% less springback than conventional room-temperature draw bending — see our Titanium Forging Guide for the equivalent process parameters when the part is hot-worked to near-net shape rather than sheet-formed.

For welding, the correct filler wire matters as much as process choice. AWS A5.16/A5.16M classifies titanium welding filler wire by ERTi-XXX code tied to base-metal grade; ERTi-5 corresponds to Grade 5/Ti-6Al-4V. That shared numbering does not by itself establish interchangeability or equivalent certification with ASTM B863 mill wire, so check the applicable spec for your product form. Process choice also has a measurable, real cost. A comparative weld study measured room-temperature tensile strengths of 958 MPa (TIG), 954 MPa (plasma-arc), 1,014 MPa (electron-beam), and 995 MPa (laser-beam) welds against 1,021 MPa base metal, with weld elongation of 7-10% versus 16.4% for the base material.

When not to specify standard-process welded Ti-6Al-4V: if your design margin depends on retained ductility near the base-metal figure, the 7-10% weld-zone elongation versus 16.4% base-metal elongation shown above is a real, quantified gap — not a rounding difference — and should be accounted for in the joint design, not assumed away.

Where Ti-6Al-4V Is Actually Used

What Each Industry Is Actually Buying Grade 5 For is rarely “strong and light” in the abstract — it’s usually one specific property driving the decision, the same way the choice between welding processes above came down to one property (ductility retention), not overall grade quality.

Beyond the applications listed in the table above, there’s demand for Grade 5 and other titanium alloys across two more heavy-engineering sectors: oil and gas (e.g., subsea hardware and processing applications) and power generation (e.g., exchanger tubes and condensers). Light weight can play a role here too, but these sectors usually demand material with very high corrosion resistance for specific service conditions. Ti-6Al-4V is widely cited as accounting for roughly half of world titanium alloy tonnage, which is why the material functions as the default comparison point for the whole titanium industry and for any other grades discussed in this guide. That means, should a supplier propose substituting a different ASTM grade for the one specified, you need to clarify which factor from the table above drove the original choice.

Standards, Specifications, and Certifications

Ti-6Al-4V is covered by a family of overlapping ASTM and AMS specifications, each scoped to a specific product form, condition, or application. Citing the wrong one — or an outdated edition — is a common and avoidable paperwork error.

Standards get revised on their own schedule, not on a fixed annual cycle — ASTM F136 jumped straight to a full 2026 edition and ASTM B348 was reissued in 2025, while ASTM B265’s current edition is still 2020. Confirm the current edition number directly against the standards body before citing one on a drawing or purchase order.

Common Questions About Grade 5 Titanium

Grade 5 Titanium Demand: What’s Actually Driving It

Grade-selection questions like the ones above are about engineering fit, but the clearest recent signal in Ti-6Al-4V’s standards landscape is external: a genuine standards-currency refresh, not a search-volume spike. ASTM F136 (the ELI implant standard) jumped to a full new 2026 edition, and ASTM B348 (bars and billets) was reissued in 2025. If you are specifying either document on a drawing or purchase order right now, the edition number is worth double-checking against the standards body directly rather than trusting an outdated internal template.

The second real driver is additive manufacturing, and it changes what buyers actually need to verify. ASTM F2924 governs powder-bed-fusion Ti-6Al-4V, and the property gap between processing routes is not small: NIST fatigue testing of electron-beam-melted (EBM) Ti-6Al-4V found as-built/stress-relieved material with fatigue endurance around 200-250 MPa, versus 550-600 MPa after hot isostatic pressing (HIP) — more than double, and specific to that AM process rather than a universal figure for every AM route. Separately, a peer-reviewed LENS (laser-based AM) study measured annealed material at 950-1050°C with yield strength around 782-789 MPa and ultimate tensile strength around 838-840 MPa, below the 900+ MPa figures typical of standard wrought mill product. The practical implication: if you’re sourcing AM Ti6Al4V, ask about post-processing condition (as-built vs. HIP’d) and powder particle-size distribution and oxygen content, not just the alloy chemistry — “titanium 6Al-4V grade 5” on an AM part’s traveler doesn’t guarantee the same properties as a wrought bar stamped with the same grade 5 6Al-4V designation.

On the demand-driver side, government sources provide more specific, dated indications than market-research CAGR numbers do (which vary significantly from company to company and are viewed here as context only, not a precise forecast). The UK government’s 2025-2035 critical-minerals demand projections estimate a total titanium demand of between roughly 91,240 and 158,800 tonnes for aerospace-related advanced manufacturing alone, as well as 544,300 tonnes for other advanced manufacturing and life science applications — these estimates cover titanium broadly and aren’t segregated for Grade 5 specifically. In the US, a 2023 Defense Production Act agreement committed $1.31 million to increase specialized titanium casting capacity for F-15, F-16, F-22, and F-35 turbine engines, although separate GAO commentary notes that defense demand for critical materials is relatively small compared to the larger global commercial market — commercial aerospace, medical, and growing additive manufacturing are the primary volume drivers.

If you’re considering a project for 2026-2027 involving Ti-6al-4v, two aspects to allocate time toward are confirming you’re citing the current standard edition and, if your supply chain or end-use touches additive manufacturing, obtaining explicit post-processing requirements before assuming a listed property value is guaranteed.

Still researching which form and condition fit your application? Once you’re ready to specify or order, TiAlloy’s Grade 5 titanium product page covers the procurement side of this material — product-form availability, mill certification and traceability, and a request-quote path — without repeating the background covered in this guide.